Sounds like either something ate them from the inside, or maybe malnutrition?

Very possibly the Narcissus Bulb Fly. they can totally scour out a bulb but usually leave the outside of the bulb intact. Some sort of insect I'm sure got a good meal from your bulbs, So sorry.... Donna

If enough of the basal plate is intact, you might be able to to put it in a nutrient bath like agar (after somehow sterilizing them). It's a really long shot, but industrial bulb companies do something similar to mass clone a bulb. You'd have to look into it though, I dunno enough about it. The basal plate is the source of all the plants roots and leaves, so if you provide a nutrient source to replace the bulb, it might rebuild itself. Even if it did, though, odds are it would be at least 3 years before it reached blooming size again.

Doesn't sound like there's any viable tissue left.